Acoustic imaging for nondestructive evaluation

The application of acoustic imaging techniques to non-destructive testing (NDT) of materials is discussed. After a description of the standard NDT techniques employed in the field and some examples of mechanically scanned imaging devices, most of the paper is devoted to a description of electronically scanned and focused systems. As holographic techniques are described by Ahmed et al. [22] in an accompanying paper, they are not discussed here. It is shown that the use of imaging techniques makes it possible to locate the position of flaws quickly and accurately.